Perhaps the reason we so often feel disappointed with God is because we think of him as a product we consume to make us feel better, instead of a father who disciplines us toward maturity. Perhaps like any good father, he allows us to feel pain in order to help us grow up.
We thought God was a magic pill to ease our pain, and it turns out he’s a real person who actually has the gall to tell us "No", as if he were some kind of authority on life. We thought if we threw the temper tantrum he would surely give us what we wanted, but he didn’t seem phased by it.
Perhaps we’d have an easier time if we reminded ourselves more often that God is our father, not a drink machine, and that growing to maturity involves learning to trust and submit to God, even when he doesn’t give us what we want.